• 文献标题:   Theory of unconventional quantum Hall effect in strained graphene
  • 文献类型:   Article
  • 作  者:   ROY B, HU ZX, YANG K
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   2469-9950 EI 2469-9969
  • 通讯作者地址:   Florida State Univ
  • 被引频次:   29
  • DOI:   10.1103/PhysRevB.87.121408
  • 出版年:   2013

▎ 摘  要

We show through both theoretical arguments and numerical calculations that graphene discerns an unconventional sequence of quantized Hall conductivity, when subject to both magnetic fields (B) and strain. The latter produces time-reversal symmetric pseudo/axial magnetic fields (b). The single-electron spectrum is composed of two interpenetrating sets of Landau levels (LLs), located at +/-root 2n vertical bar b +/- B vertical bar, n = 0,1,2, . . ..For b > B, these two sets of LLs have opposite chiralities, resulting in oscillating Hall conductivity between 0 and -/+ 2e(2)/h in electron and hole doped systems, respectively, when the chemical potential is tuned in the vicinity of the neutrality point. The electron-electron interactions stabilize various correlated ground states, e.g., spin-polarized, quantum spin Hall insulators at and near the neutrality point, and possibly the anomalous Hall insulating phase at incommensurate filling similar to B. Such broken-symmetry ground states have similarities as well as significant differences from their counterparts in the absence of strain. For realistic strength ofmagnetic fields and interactions, we present scaling of the interaction-induced gap for various Hall states within the zeroth Landau level. DOI: 10.1103/PhysRevB.87.121408